FIG. 1 schematically illustrates a known circuit diagram of an array substrate for touch control functionality.
In the existing techniques, a common electrode layer is divided into a plurality of independent units each of which serves as a touch control electrode P.
In FIG. 1, except for dotted lines connected with touch control detection terminals T, elements in FIG. 1 constitute an equivalent circuit diagram of a liquid crystal display device. Each touch control electrode P in the equivalent circuit includes a plurality of Thin Film Transistors (TFTs).
Referring to FIG. 1, impulse signals g1 to gn are connected to corresponding scanning lines. Each scanning line connects gates of TFTs in a plurality of sub pixels in one row. The scanning lines are configured to turn on or turn off the TFTs of the sub pixels.
Data input terminals W are connected to corresponding signal lines which are arranged in columns. Each signal line connects drains or sources of TFTs of a plurality of sub pixels in one column The signal lines are configured to transmit signals to pixel electrodes of the sub pixels.
Capacitance Cst represents the equivalent capacitance of an electric potential of a common electrode (i.e., COM electric potential) and other electric potentials.
In the existing techniques, touch control function and display function are integrated by dividing the common electrode layer into a plurality of independent units. Specifically, each touch control electrode P corresponds to a detection capacitance CM and a detection signal line (represented by a dotted line) connected with the detection capacitance CM. A touch control detection terminal T detects the variation of the detection capacitance CM to determine a touched region. The above-mentioned detection method is widely adopted and is referred to as the self-cap touch control method.
However, in the self-cap touch control method, to realize signal detection, a plurality of detection capacitances CM are required in the whole array substrate, and each detection capacitance CM needs to be connected with a detection signal line. As a result, wiring density and production processes are increased. When a large size of a display panel or high-accuracy touch control is required, the number of detection signals connected with detection capacitances may be relatively great, which makes the wiring of the display panel more difficult. In addition, the detection capacitances vary from one another. Therefore, it is difficult to obtain a display panel having a large size or a display panel having high accuracy in touch control.